Type-writing machine.



No. 636,709. Patented Nov. 7, I899. E. M. BENNETT. TYPE WRITING MACHINE.

(Application filed Aug. 4, 1898.)

(No Model.)

l I A JHUGHZOP WDZ/765565 Va. @Wnwtb W6. W g QM 1 MW EMMET M. BENNETT, OF BALTIMORE,

PATENT OFFICE.

MARYLAND, ASSIGNOR OF ONE-HALF TO HARRY L. BEAN, OF SAME PLACE.

TYPE-WRITING MACHINE.

SPECIFICATION forming part of Letters Patent No. 636,709, dated November '7, 1899.

Application filed August 4, 1898.

T on whom it may concern:

Be it known that I, EMMET M. BENNETT, a citizen of the United States, residing at Baltimore, in the State of Maryland, have invented certain new and useful Improvements in Type-Writing Machines, of which the following is a specification.

This invention relates to improvements in attachments for type-writing machines.

It consists, as hereinafter fully described, in certain mechanism used in connection with spring-actuated paper-carriages whereby the carriage may be returned or moved back step by step one space at a time or to the point where the last letter or any particular letter has been printed, whereby a letter may be reprinted or another letter printed in the same space already having the impression of the type.

In the accompanying drawings, Figure 1 is a side elevation of the frame of a type-writing machine, showing the relative position of the improved mechanism. Fig. 2 is a view, on a larger scale, of the escapement-wheel, rack, and pinion for letter-spacing, and also shows the improved mechanism for back spacing. Fig. 3 is a section on line 3 3 of Fig. 2. Fig. 4 is a plan view of the improved mechanism as it appears on a type-writing machine. Fig. 5 is a cross-section on the line 5 5 of Fig. 2.

The invention is designed to be attached to any of the well-known makes of type-writing machines where spring-actuated paper-carriages are employed. It may be readily attached to machines now in the hands of users.

In the drawings the letter A designates the frame of the machine,and h b bearings mounted on top of the frame. A shaftc is mounted in the bearings 17 b and carries at one end a pinion d, which engages a rack e, attached to the paper-carriage, whereby the spring-actuated movement of the carriage is communicated to the shaft 0 through the rack and pinion d. At the other end of the shaft 0 is an escapement-wheel d, by means of which the step-by-step motion for the purpose of forward letter-spacing is accomplished by the operation of the ordinary space-bar and levers. 50 The parts thus far described are old and are fierial No. 637,717. (No model.)

found on various machines now in use and do not comprise any part of my attachment.

A ratchet-wheel E is fixed on the shaft 6 between the two bearings 12 b and revolves with said shaft. At each side of the ratchet- 5 wheel is an arm f,loosely mounted on the shaft and free to oscillate. Said two arms carry a pawl g, which is normally out of engagement, but in operation engages the ratchet-wheel E. The pawl g at the top has two projecting cars 66 g to receive the rod h, which is connected therewith, so as to allow of an oscillatory motion of the arms. A stop-shoulder g on the pawl engages a stop-pin g on the arm f. The rod hat it other end is pivoted to an arm t'of a rock-shaft i,and another arm 11 of said rock shaft is pivoted to a vertical rod j. The verti cal rod 3' has a screw device to permit of Vertical adjustment, shortening, or lengthening of the rod, so as to regulate the extent of throw of 7c the rock-shaft. The lower end of the Vertical rod j is connected to a bar 70, which in turn is pivoted near one end to a projection Z at the front of the machine.

An ordinary key m and key-bar m, fulcrumed at the back of the machine, connect with the said bar It by a link it. This key is the back-spacing key.

The operation is as follows: Suppose the operator in writing fails to hit a key hard enough to make a good impression, but the carriage nevertheless moves along one letterspace, or for some other reason the operator desires to move the carrage back one space. Instead of removing the hands from the keyboard and delicately adjusting the carriage so as to move it back one space, the operator simply depresses the back-spacing key m, and thereupon the key-bar m pulls down the bar 70, the vertical rod j, and rock-arm 1?, turns the rock-shaft 2", moves back the rock-arm 11 and rod h, and draws the pawl g, which revolves the ratchet-wheel E, shaft 0, and pinion d,which finally moves the rack e and carriage back one space. The arms fhave a flat or angular bottom f, and a spring 1" presses against this flat bottom to cause the pawl to be returned to its normal position after it has been drawn by the rod h.

I am aware that prior to my invention type writers had been patented in which provision was made for a stcp-by-step movement of the paper-carriage backward by repeated depressions of a key, and I do not herein claim such to be my invention. My claim relates to the improved construction of parts shown by which they may be attached to old machines now in use.

Having thus described my invention, what I claim is A back-spacing attachment for type-writing machines having a spring-actuated papercarriage provided with a rack,e, and a shaft,c, mounted in bearings on top of the machine and. carrying at one end a pinion engaging said rack and at the other end an escapementwheel, 01, said attachment comprising a ratchet-wheel, E, mounted on the said shaft between the pinion and escapement-wheel; arms, f, loosely mounted on the shaft at the sides of the ratchet-wheel and free to oscillate; a pawl carried by said arms and engaging the ratchet-wheel when it is desired to move the carriage back, but normally out of engagement with the ratchet-wheel; a rockshatt, i, mounted on top of the machine; a rod connecting the said pawl with the rockshaft; and means connecting between the said rock-shaft and a key, substantially as set forth.

In testimony whereof I affix my signature in the presence of two witnesses.

EMMET M. BENNETT.

W'itnesses:

CHAPIN A. FERGUSON, CHARLES B. MANN, Jr. 

